Adjustable self-locking wrench

ABSTRACT

A WRENCH HAVING A FIXED AW ON A HANDLE AND A MOVABLE JAW OPERATED BY A CONTROL LEVER PIVOTED ON THE HANDLE, THE MOVABLE JAW HAVING A DOVETIAL PORTION MOUNTED IN A DOVETAIL SLIDE IN THE HANDLE AND ADAPTED TO WEDGE AND LOCK THEREIN WHEN TURNING PRESSURE IS APPLIED BY THE   WRENCH UPON A WORKPIECE. SPRING MEANS ACT UPON THE CONTROL LEVER TO BIAS THE MOVABLE JAW TOWARD THE FIXED JAW.

United States Patent 3,563,118 ADJUSTABLE SELF-LOCKING WRENCH Edmund W. F. Rydell, The Rydell C0., 2328 N. 2nd St., Minneapolis, Minn. 55411 Filed Apr. 24, 1968, Ser. No. 723,795 Int. Cl. B25b 13/12 U.S. Cl. 81-129 7 Claims ABSTRACT OF THE DISCLOSURE A wrench having a fixed jaw on a handle and a movable jaw operated by a control lever pivoted on the handle, the movable jaw having a dovetail portion mounted in a dovetail slide in the handle and adapted to wedge and lock therein when turning pressure is applied by the wrench upon a workpiece. Spring means act upon the control lever to bias the movable jaw toward the fixed jaw.

The invention relates generally to wrenches which can be readily adjusted to engage different sized workpieces and which then automatically lock in adjusted position when the wrench is used to apply turning pressure to the workpiece. Such a wrench is disclosed in my earlier U.S. Letters Patent No. 3,322,009, issued May 30, 1967. The present invention contains certain improvements in the type of wrench described in said patent.

An object of the present invention is to provide a selflocking wrench having a movable jaw mounted in a slide and with the jaw and slide having plural broad intermating binding areas to prohibit jaw slippage.

Another object of the invention is to provide a wrench having an automatic friction locking movable jaw which will not slip even though the friction locking surfaces be coated with lubricant.

Still another object of the invention is to provide a selflocking wrench wherein the locking is provided by counteracting wedging forces so as to prohibit distortion of the wrench components under heavy pressures.

Another object of the invention is to provide a wrench which may be instantly adjusted to and locked upon a workpiece of any normal size without conscious adjusting effort on the part of the user.

Still another object is to provide a wrench which may be adjusted and operated completely by one hand, and by either hand, of the operator while the hand is in normal wrench turning position.

Another object is to provide an adjustable wrench which can easily and readily be adjusted to a workpiece even though it be located in a very confined area.

The above mentioned and additional objects of the invention will be brought to light during the course of the following specification, reference being made to the accompanying drawing, in which- FIG. 1 is a plan view of the first embodiment of the wrench in gripping engagement with a nut. The wrench handle is partially broken away to show the control lever and other features of the wrench construction are denoted by broken lines.

FIG. 2 is an enlarged plan view of the wrench head broken away to show the movable jaw in wedged and locked position.

FIG. 3 is a section through the movable jaw and slide taken on line 33 of FIG. 2.

FIG. 4 is a plan view of a second embodiment of the wrench head with certain features of the construction shown in broken lines.

Referring now more particularly to the drawing reference numerals will be used to denote like parts or structural features in the different views. The wrench has three main components here designated generally as a 3,563,l18 Patented Feb. 16, 1971 ice body member 21, a movable jaw member 22, and a lever or control member 24. The body member 21 comprises an elongated handle 25 having a head 26 at one end which includes a fixed or integral jaw 27 provided with a flat 5 gripping face 28. The head 26 is relatively narrow and is provided with a narrow opening or slideway 29 extending therethrough in a direction perpendicular to the jaw face 28. Opening 29 communicates with an elongated chamber 30 in the handle 25 which opens through the bottom side thereof as the wrench is viewed in FIG. 1.

The movable jaw member 22 fits in the opening 29 for movement toward and away from jaw 27 in a manner shortly to be described. This member 22 is provided with a hook portion 31 having a notch 32 opening rearwardly or toward the chamber 30. The lever member 24 is formed of relatively flat material and has an ear portion 34 near the longitudinal center thereof which is pivoted to the handle as by pin 35. To the rear of the pivot 35 a finger grip 36 is formed at one side of the lever and a spring seat 37 on the other for securing spring 38 between the handle and lever under compression to urge the members apart. The forward end of lever 24 is formed with a tapered finger 39, the end of which fits in notch 32 providing a flexible connection between the jaw member 22 and lever 24.

The design of the movable jaw member 22 and its mounting in the body member 21 will now be described in greater detail. The jaw has a fiat gripping surface 40 disposed in opposing spaced relation and parallel to the face 28 on the jaw 27 so that a parallel sided workpiece such as the nut N may be securely gripped therebetween. On its inner end and within the opening 29 the member 22 has a mounting flange 41 which is shaped in cross section as shown in FIG. 3. The heretofore mentioned hook portion 31 is formed in the lower portion of flange 41. The inner or rear edge portion 4 2 of the flange 41 has a cross sectional dovetail shape having a sliding fit in the inner portion 44 of opening '29 which has a similar cross sectional shape.

The leading end of wrench head 26 below the integral jaw 27 has transversely spaced forwardly tapering wedgeshaped edges 45 disposed on each side of the opening 29 extending the entire depth of the head below the integral jaw, thus leaving a dovetail-shaped opening 46 therebetween. Member 22, at its juncture with flange 29, is formed as shown in FIG. 3 with. a pair of transversely spaced rearwardly opening V-shaped grooves 47 respectively seating the wedge-shaped edges 45 and leaving a portion 48 therebetween which seats against the opening portion 46.

A web 49 connects the movable jaw surface 40 with the portion 48 of flange 41 above the surface 40 so as to keep the workpiece N well out on surface 40. The opening 29 on head 26 is provided with a relief 50- to receive the web 49 when the wrench is closed.

It will be understood that flange 41 has a sliding fit in the opening 29 with the diverging side walls of the rear edge portion 42 mating with and opposing the rearwardly diverging side walls of the opening portion 44. Similarly, the V-shaped grooves 47 in the movable jaw 22 will mate with and slide along the wedge-shaped edges 45.

The jaw portion 42 has a chamber 54 formed near the bottom thereof opening rearwardly toward the spaced rear walls 55 of the opening 29 as can be observed in FIG. 2. A small plate spring 56 is disposed in the chamber 54 and has its rear leg widened to engage against both of the walls 55 to hold the spring under compression and urge the lower portion of jaw 22 in a forward direction.

Operation of the wrench will now.be understood. In non-use or stored condition the movable jaw 22 will be held closed against the jaw 27 under the closing force exerted by spring 38 through lever 24.

When the user wishes to grip the workpiece N and turn it in the direction indicated by the arrow in FIG. 1, he manually squeezes against lever portion 36 to compress spring 38 and swing the finger portion 39 of lever 24 in a direction away from the fixed or integral jaw 27. This, of course, will move the movable jaw 22 away from jaw 27. The flange 41 and its associated beveled jaw portions 44 and 48 will not stick or bind in the opening 29 during the jaw separating movement because the finger 39 is coupled to member 22 on substantially the center axis of the path of movement of the flange. Also the spring 56 functions to urge the grooves 47 on member 22 away from the wedgeshaped edges 45 so as to prevent binding therebetween during opening movement of the jaws.

After the jaws have been separated a sufiicient distance to receive the workpiece N therebetween, the squeezing grip on lever portion 36 is released allowing spring 38 to take over and move the jaw 22 in a closing direction until the workpiece N is clamped between the jaw surfaces 28 and 40. Jaw 22 then tilts slightly, as shown in exaggerated condition in FIG. 2, bringing the upper area of flange portion 42 into forward wedging engagement with the walls of opening 44 and the V-shaped grooves 47 into engagement with the wedge-shaped edges 45. Each of these mating surfaces bind over a fairly large area and the front and rear binding surfaces on the movable jaw are relatively widely separated.

The wedging surfaces are disposed at approximately a fifteen degree angle to the longitudinal center line of the wrench and this angle is found to prevent slippage while yet allowing the movable jaw to come loose after having been subjected to relatively heavy force.

The forces generated perpendicular to the wedging surfaces are very high. It is accordingly necessary to design the Wrench to prevent spreading of the walls providing the wedging surfaces on either side of the opening 29. This is accomplished by the interlocking fit of the wedges 45 and grooves 47 providing four equal and counteracting wedging surfaces.

A slightly different form of the invention is shown in FIG. 4. The body member 21 is identical to that in the first embodiment. The movable jaw 62 is identical in all respects to jaw 22 excepting only that the hook portion of the jaw extends rearwardly beyond the jaw mounting flange as at 64 and has a notch 65 for seating the forward end of the control lever 66. Accordingly in this embodiment the coupling between the control lever and jaw is rearwardly offset from the center axis of the path of movement of the jaw mounting flange. Except for the shortened length the lever 66 is identical to and mounted on the body member 21 in the same manner as the lever 24.

In this form of the invention, as the lever 66 is operated the jaw 62 will slide freely in the head 26 with the small spring 56 forming the same function of urging the lower portion of jaw 62 forwardly. However, once the jaws are clamped upon a workpiece such as the nut N, the various binding surfaces will come into engagement under pressure of the control lever spring 38. However, in this embodiment when the wrench is withdrawn from the workpiece it will remain at the adjusted setting so that it may be reapplied to the workpiece without again squeezing the control lever. This is due to the strong force of the lever spring 38 which, because of the offset connection at 65, tends to tilt the jaw rather than move it axially along the slide pathway as in the first embodiment.

When the user wishes to release or unlock the jaw 62, he merely squeezes the control lever to free the jaw from its bound condition and spring 56 will again act upon the jaw to prevent the lower binding surfaces from touching as the jaws are opened and closed.

I have accordingly provided a wrench construction which economically and effectively carries out the aforementioned objectives. It is understood that suitable modifications may be made in the structure as disclosed, provided such modifications come within the spirit and scope of the appended claims.

Having now therefore fully illustrated and described my invention, what I claim to be new and desire to protect by Letters Patent is:

1. In a wrench (a) a wrench body having a head at one end of an elongated handle,

(b) an integral jaw on the head having a flat gripping face,

(c) said head having a slideway formed therein extending perpendicular to said face,

(d) the slideway having a pair of facing walls spaced transversely of the handle which converge in a direction longitudinally of the handle to give a portion of the slideway a dovetail shape in cross section,

(e) a movable jaw arranged in opposing relation to the integral jaw,

(f) said movable jaw having a wedge-shaped portion disposed in said slideway portion for sliding movement therealong,

(g) said wedge-shaped portion having converging slide walls respectively mating with and facing the said slideway walls with all of said walls being disposed at approximately a fifteen degree angle to the longitudinal center line of the wrench to wedge against each other when tilting pressure is applied to the movable jaw in a direction away from. the integral J (h) an elongated lever pivoted at a radial point to the handle on an axis perpendicular to the slideway,

(i) means providing a flexible connection between the movable jaw and one end of the lever,

(j) spring means held under compression between the other end of the lever and the handle to bias the movable jaw in a direction toward the integral jaw.

2. The subject matter of claim 1 wherein a second spring means is disposed between the movable jaw and head to yieldably hold said walls out of wedging engage- 0 ment.

3. The subject matter of claim 1 wherein said flexible connection is located substantially on the center axis of said slideway.

4. In a wrench (a) a wrench body having a head element at the forward end of an elongated handle,

(b) said head element including an integral jaw having a generally fore and aft extending gripping surface,

(c) said head having a slideway formed therein extending perpendicular to said surface,

(d) a movable jaw element arranged in opposing relation to the integral jaw,

(e) said movable jaw element having a flange provided with an enlarged portion disposed in said slideway for movement of the movable jaw on a path normal to said surface toward and away from the fixed jaw,

(f) a control lever extending longitudinally of the handle and having its forward end flexibly connected to the movable jaw element,

(g) said lever pivoted to the handle for swinging movement of said forward end of actuate said sliding movement of the movable jaw element,

(h) spring means acting between the handle and lever to bias the movable jaw element toward the fixed jaw,

(i) one of said elements having a pair of tapered wedge-shaped edges transversely spaced with respect to said path of movement and extending parallel thereto,

(j) the adjacent walls of said wedge-shaped edges diverging and the remote walls thereof converging toward the edges,

(k) the other of said elements having a pair of parallel V-shaped grooves mating with and seating said edges and relatively slidable therealong during sliding movement of the movable jaw element so that said edge walls and groove walls are adapted to frictionally bind against each other when tilting pressure is applied to the movable jaw element in a direction away from the fixed jaw, and

(1) a second spring means interposed between said elements yieldably biasing said movable jaw element in a direction opposite to said direction of tilting pressure to prohibit said frictional binding during sliding movement of the movable jaw element.

5. The subject matter of claim 4 wherein the movable jaw element is provided with a rearwardly opening chamber and said second spring means comprises a leaf spring disposed within said chamber and held under compression between a rearwardly facing wall of the movable jaw element and a forwardly facing wall of the head element.

6. In a wrench (a) a wrench body having a head at one end of an elongated handle,

(b) an integral jaw on the head having a flat gripping face,

(c) said head having a slideway formed therein extending perpendicular to said face,

(d) the slideway having a pair of facing walls spaced transversely of the handle which converge in a direction longitudinally of the handle to give a portion of the slideway a dovetail shape in cross section,

(e) a movable jaw arranged in opposing relation to the integral jaw,

(f) said movable jaw having a wedge-shaped portion disposed in said slideway portion for sliding movement therealong,

(g) said wedge-shaped portion having converging side walls respectively mating with and facing the said slideway walls to wedge thereagainst when tilting pressure is applied to the movable jaw in a direction away from the integral jaw,

(h) an elongated lever pivoted at a radial point to the handle on an axis perpendicular to the slideway,

(i) means providing a flexible connection between the movable jaw and one end of the lever,

(j) spring means held under compression between the other end of the lever and the handle to bias the movable jaw in a direction toward the integral jaw,

(k) said flexible connection being spaced toward the handle from the center axis ofsaid slideway.

7. In a wrench (a) a wrench body having a head at one end of an elongated handle,

(b) an integral jaw on the head having a flat gripping face,

(c) said head having a slideway formed therein extending perpendicular to said face,

((1) the slideway having a pair of facing walls spaced transversely of the handle which converge in a direction longitudinally of the handle to give a portion of the slideway a dovetail shape in cross section,

(e) a movable jaw arranged in opposing relation to the integral jaw,

(f) said movable jaw having a wedge-shaped portion disposed in said slideway portion for sliding movement therealong,

(g) said wedge-shaped portion having converging side walls respectively mating with and facing the said slideway walls to wedge thereagainst when tilting pressure is applied to the movable jaw in a direction away from the integral jaw,

(h) an elongated lever pivoted at a radial point to the handle on an axis perpendicular to the slideway, (i) means providing a flexible connection between the movable jaw and one end of the lever,

(j) spring means held under compression between the other end of the lever and the handle to bias the movable jaw in a direction toward the integral jaw,

(k) said slideway having two pair of said converging walls to form two of said dovetail portions in the slideway which are spaced apart in the same direction as the wall convergence,

(1) and said wedge-shaped portion of the movable jaw having two pairs of said converging side walls each pair mating with a pair of said slideway walls and adapted to respectively wedge thereagainst.

References Cited UNITED STATES PATENTS 1,975,908 10/1934 Swanson 81356 2,156,529 5/1939 Day 81359 3,322,009 5/1967 Rydell 81359 ROBERT C. RIORDON, Primary Examiner R. V. PARKER, JR, Assistant Examiner US. Cl. X.R. 

